Heat a large skillet over medium heat and add a splash of olive oil. Once hot, toss in minced garlic and chopped onion, cooking for about 3–4 minutes until the onions become translucent and fragrant.

Add the ground beef to the skillet, breaking it apart with a spatula. Season with Italian seasoning, salt, and pepper, allowing it to brown for about 5–7 minutes until no longer pink.

Once the beef is fully cooked, lower the heat and stir in the creamy tomato sauce. Bring to a gentle simmer and let it bubble for about 3 minutes.

In a separate pot, bring salted water to a boil. Cook the medium pasta shells according to package instructions, usually about 8–10 minutes for al dente.

Add the drained pasta shells to the skillet with the sauce and beef mixture. Toss gently to ensure the pasta is well-coated, adding reserved pasta water if necessary.

Sprinkle shredded cheddar cheese on top and let it melt for a minute before serving.